A Biomechanics and Imaging (B&I) Core is proposed to provide sophisticated technical support to all three CORT projects. Post-traumatic osteoarthritis (PTOA) results from mechanical insult to articular cartilage, and it is frequently evaluated based on a variety of imaging features. The members of the Core have an established history of developing mechanics and image analysis methodologies for quantifying particular observations of interest. The B&I Core will support the three CORT projects by achieving two specific aims. The first aim of the Core is to serve as a general technical resource comprised of advanced hardware, image analysis protocols, and personnel experienced in developing and conducting biomechanical and imaging studies. These general capabilities will be utilized as needed by the different CORT projects to support and complement both ongoing and newly evolving project activities. The second aim of the Core is to provide expert support in the areas of mechanics and image analysis which specifically enhances the work in the three CORT projects. These specialized activities can be broadly classified into four main types: computational mechanics/modeling; physical measurement and hardware design; quantitative MRI analysis; and quantitative evaluation of microscopic-level images. This variety of multidisciplinary activities best fits within the structure of a core that can support all three CORT projects simultaneously. The B&I Core provides an explicit point of overlap between the various aims of the three research projects, which allows for opportunities for the different projects to inform each other better than if the individual Core activities were segregated in the different projects. A combined mechanics and imaging core also facilitates development of unique multi-modal (e.g. stress analysis and imaging) and multi-scale (e.g. histological to clinical) imaging comparisons, which are critical to translating basic research into the clinical setting.